Lightweight Antivirus programs.

I agree that for home user's buying Sophos isn't a option as it's insanely expensive, I didn't realise it was over ?100 for a single user the last time I saw it advertised it was about ?65..... I use it at home but that's because the University I work for has it licensed.

Continuing on from how well Sophos will perform on older PC's, I've installed the new V4.5 for NT and Win 9x on a 150mhz CPU with 64mb (Win NT) and a 233mhz CPU with 64mb (Win 98). As far as I can tell there has been no performance decrease from when these PC's had V3.xx installed.

I concur with your statement about McAfee Enterprise as we use that as well at work and that is also very light on system resources.

Command or Authentium is primarily an Enterprise AV and has become more so of late. Further, it took their support over 2 months to send me a serial number to trial the Home version. Frisk and Dr Web are very slow in pushing out relevant upgrades to the program and it takes them a long time to fix any bugs. Similarly, VBA32 seem to be treading water, as most small vendors are, in simply keeping up with adding new signatures never mind looking at new features. All 5 remain lightweight but IMHO, there are now much better alternatives.

Norton's last 2 efforts have been superb and recent testing over at av-comparative and av-test org (December, 2009) places it at or near the top for detection.

But it is worth considering the following;

1. Cloud computing seems to be "the next big thing" and I have been very impressed with Prevx/Prevx SafeOnline which is very lightweight and Forum support over at Wilders Security is superb; http://www.prevx.com/

2. A free cloud AV which has recently come out of beta is Panda Cloud AntiVirus which again is very lightweight but has had too many bugs for me, particularly on Vista; http://www.cloudantivirus.com/en/ But well worth keeping an eye on.

3. HitMan Pro is also worth considering; another cloud product which uses the scan engines of Avira, Eset, G-Data, Prevx and A-squared and free as an on-demand scanner; http://www.surfright.nl/en/hitmanpro

4. The standard of the free AV programs has improved considerably over the last year or so; Microsoft Security Essentials is a very simple but effective program. fast scanner and its detection rate/malware removal abilities have already been tested and proven to be top notch. But some updating bugs still need to be solved on some systems, particularly laptops coming out of standby/sleep modes.

5. Panda's Cloud AV I have already mentioned and the new Avast 5 beta seems very promising; VERY lightweight footprint due to an excellent caching mode and great features/options which you do not find in many commercial AVs; http://forum.avast.c....php?board=15.0

Overall, I would say now that a free AV together with some more layered protection such as a Sandbox/HIPS and a good imaging program should keep most users safe from malware.

When some of the new additions above have matured and I have more experience with them I will add some more detailed information.

Still running AVs on separate snapshots on my one remaining 32-bit machine.

Over the last year after testing many AVs, my present recommendations would be;

Free AV- Avast. The new version 6 now has a sandbox and a script checker. Very, very light on CPU performance. With Avast Free, who needs to buy an AV now?

Paid AVs- Prevx, Vipre and TrustPort-all lightweight, particularly TrustPort which after fingerprinting/caching is the lightest AV I have ever used in terms of effect of performance, CPU time, I/O Reads and Writes.

Overall recommedation; use Avast Free and AppGuard/Defensewall as an excellent layered defense.

WSA and Trustport are probably the lightest two I have tried and you can get excellent deals on WSA by buying the 2011 versions on ebay and upgrading to the latest 2012 versions. Ikarus at the present time has a 50% discount for Wilders Security members.

Today I would recommend running an AV together with a sandbox program or an Anti-executable.